Threshing cylinder bar



Aug. 31, 1965 w. s. AUSHERMAN 3,203,428

THRESHING CYLINDER BAR Filed June 21, 1963 IIIIIIII/ 7 "III/I4 INVENTOR. mil WILLIAM s. AUSHERMAN BY 45M ATTORNEY United States Patent 3,203,428 THRESHING CYLINDER BAR William S. Auslrerman, 3500 N. Topeka, Wichita, Kans. Filed June 21, 1963, Ser. No. 289,496 Claims. (Cl. 130-27) The present invention relates to new and useful improvements in cylinder bars such as are used in the threshing cylinders of combines, and more particularly pertains to the cylinder bars so modified as to prevent or greatly reduce the accumulation of trash on the sides thereof disposed toward the axis of the threshing cylinder Conventional cylinder bars, whether of the integral or composite type, are recessed on the side thereof facing toward the axis of the threshing cylinder so as to present a cavity underlying the teeth and intermediate the latter margins of the bar that opens toward the axis of the threshing cylinder. An undesirable consequence of such construction is that trash tends to accumulate in such cavities, with such trash tending to be retained in such cavities by centrifugal forces. Very rough cylinder operation can result from such accumulation of trash for the reason that the rate trash accumulation among the various bars can be very unequal, and the rate of trash accumulation along the length of a single cylinder bar can be far from uniform, whereby static and dynamic imbalance of the cylinder causes excessive vibration, hearing wear, etc.

The cylinder imbalance referred to in the preceding paragraph is further aggravated with great abruptness and deleterious effects inasmuch as the trash accumulations of one or more bars or portions of bars occasionally become dislodged without advance Warning to the operator of the harvesting machine.

Both the frequency and the severity of conditions of imbalance are functions of a plurality of variables, among which the most notable is the moisture content of the material or fields being threshed.

In view of the foregoing, the primary aim of the invention is to prevent or minimize imbalance of threshing cylinders occasioned by the cylinder bars accumulating and/or accumulating and abruptly discharging accumulated trash.

Another aim of the invention is to provide cylinder bars that are reversible and which will be resistant to the accumulation of trash as well as abrupt dislodgement of accumulated trash.

Another aim of this invention is to provide in acordance with the aims previously set forth an improved cylinder bar which can be of integral construction, or of composite construction.

Yet another aim of the invention is to provide a cy1- inder bar that is reinforced to resist flexure along its length, and which cylinder bar will tend to resist the accumulation of trash as well as sudden dislodgment of accumulated trash.

Still another aim of the invention is to provide a cylinder bar of composite construction that will tend to resist the accumulation of trash as well as sudden dislodgement of accumulated trash, and which cylinder bar will include as a replaceable component thereof a reversible rasp bar such as that disclosed in my US. Patent No. 3,034,513, entitled Reversible Bar for Threshing Cylinders that issued May 15, 1962.

Broadly, the invention has to do with a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly offset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying 3,12%,428 Patented Aug. 31, 1965 the rasp bar that is laterally bounded by adjacent margins of the flanges, the same being improved by having in combination therewith means for reducing the accumulation of trash in said cavity comprising at least one of such flanges being provided with a longitudinally extending row of openings therethrough, said openings being disposed adjacent the junction of such flange with the rasp bar and opening into said cavity.

Another aspect of the invention involves the provision of a rasp bar such as defined in the preceding paragraph, wherein openings are provided in each of the flanges, with the openings in the flanges being in transverse alignment.

Yet another aspect of the invention involves the provision of the rasp bar such as defined in the last two paragraphs, wherein the rasp bar includes a medical rib depending into said cavity, such rib being provided with a row of openings in alignment with the openings in the flanges.

Yet another aspect of the invention involves the provision of a rasp bar provided with openings in the flanges for ventilating the cavity, wherein the rasp bar construction includes a detachably secured rasp bar such as disclosed in my previously mentioned patent, whereby replacement may be made of the only portion of the rasp construction that is susceptible toany appreciable wear.

The invention will be most readily understood in the light of the following specification taken in conjunction with the accompanying drawings illustrative of preferred embodiments of the invention, wherein:

FIGURE 1 is a side elevational view of a threshing cylinder provided with the improved cylinder bars of this invention;

FIGURE 2 is an end elevational view of the threshing cylinder in FIGURE 1;

FIGURE 3 is a top plan view of one of the cylinder bars shown in FIGURES 1 and 2, this view being taken on an enlarged scale;

FIGURE 4 is a transverse vertical sectional view taken upon the plane of the section line 44 shown in FIG URE 3, this view being taken upon a still further enlarged scale;

FIGURE 5 is a fragmentary vertical sectional detail view taken upon the plane of the section line 5-5 in FIGURE 4;

FIGURE 6 is a transverse vertical sectional view of a modified embodiment of the cylinder bar; and

FIGURE 7 is a vertical transverse sectional view of another embodiment of the cylinder bar.

Referring now to the drawings, wherein like numerals designate like parts throughout the various views, and with attention being first directed to FIGURES 1 through 5, inclusive, the reference numeral 10 designates generally a threshing cylinder such as is used in association with the concaves and associated mechanism of conventional threshing machinery.

The threshing cylinder 10 comprises a central longitudinal shaft 12 by means of which rotation is imparted to the cylinder 10 by conventional means, not shown. Disk-shaped cylinder end walls 14 and 16 are secured to mounting flanges 18 by bolts 20 (see FIGURE 2), with the mounting flanges 18 being in turn non-rotatably secured to the shaft 12 by conventional means.

The cylinder 10 also includes a plurality of longitudinally extending, circumferentially spaced cylinder bars such as those designated generally at 22 and 24 in FIG- URE l. The disk-like cylinder end walls 14 and 16 respectively include axially extending peripherally flanges 26 and 28, as is conventional, and the cylinder bars 22 and 24 are secured to the flanges 26 and 28 by means of cap screws 30 and 32 that extend through the cylinder bars 22 and 24 adjacent the lateral edges of the latter. The structure of the cylinder is further stabilized by means of a reinforcing ring 34, which may be disc-shaped, as is conventional, with the cylinder bars 22 and 24 being secured to the ring 34 by means of cap screws 36 that extend through the cylinder bars 22 and 24 adjacent the lateral edges of the latter.

It is to be noted that the cylinder bars 22 and 24 shown in FIGURE 1 are identical except for the fact that they are shown reversed end for end with respect to each other. It will also be noted that the cylinder 10 includes an even number of cylinder bars, and it is to be understood that all of the cylinder bars are identical to the cylinder bar 24 shown in FIGURE 3 with alternate bars being reversed end for end. The advantages-accruing from the alternately reversed positions of the cylinder bars 24 on the cylinder 10 will become apparent upon reference to my hereinbefore mentioned US. Patent No. 3,034,513 in the light of the following description of the cylinder bar 24 as best shown in FIGURES 3 through 5, inclusive.

As shown in top plan view in FIGURE 3, the cylinder bar 24 has lateral marginal portions 40 and 42 extending the entire length of the cylinder bar 24. An intermediate portion of the lateral extent of the cylinder bar 24 defines a longitudinally extending row of two sets of upstanding teeth 44 and 46. Generally speaking, the intermediate portion of the lateral extent of the cylinder bar 24 defining the sets of teeth 44 and 46 is similar to the rasp bar disclosed in my previously mentioned US. Patent No. 3,034,513, with the individual teeth of the sets of teeth 44 and 46 being oppositely inclined with respect to the transverse extent of the cylinder bar 24 and with the opposite lateral extremities of each of the teeth being beveled as indicated at 48 through 54 inclusive. The upper extremities of the individual teeth of the sets of teeth 44 and 46 terminate substantially in a plane, or preferably in a cylindrical surface concentric with the axis of the shaft 12. The upper surface of the cylinder bar along its longitudinal extent and spaced intermediate the lateral extremities of the individual teeth of the sets of teeth 44 and 46 is smoothly raised at 55 in a manner such as disclosed in my US. Patent No. 3,034,513, so that the teeth are effectively of shorter length intermediate their lateral extents. Also, as described in my previously mentioned US. Patent No. 3,034,513, the juncture of the two sets of teeth 44 and 46 is displaced longitudinally from the midpoint of the cylinder bar 24, with the juncture of such two sets of teeth being defined by a single V-shaped tooth 56. The purpose of the juncture between the two sets of teeth 44 and 46 being displaced longitudinally from the midpoint of the longitudinal extent of the rasp bar 24 is that during rotation of the cylinder bars with alternate cylinder bars being reversed end for end successive junctures do not track each other. This arrangement with alternate bars being reversed promotes the even spread of material being threshed along the length of the cylinder 10 and tends to promote even wear of teeth throughout the length of the cylinder bars and especially in the region of the juncture of the oppositely inclined sets of teeth 44 and 4 6. Furthermore, as will be seen presently, the rasp bar 24 is symmetrical about a central vertical plane, whereby each cylinder bar 24 can be reversed end for end after the edges of the teeth that had been leading during rotation of the cylinder 10 have become worn, whereby the wearing life of the cylinder bar can be greatly extended.

Directing attention now to FIGURE 4, it will be seen that the lateral marginal portion 40 of the cylinder bar 24 is comprised of an L-shaped flange that includes a depending leg 60 that diverges slightly downwardly from the longitudinal central vertical plane of the cylinder bar 24, and an integral outwardly extending and generally horizontal leg 62. The L-shaped flange defined by the legs 60 and 62 are integral with each other and with the web portion 64 of the cylinder bar 24 that underlies the sets of teeth 44 and 46. The lateral marginal portion 42 of the cylinder bar 24 is defined by a generally L-shaped flange that includes a depending leg 66 and an outwardly extending and generally horizontal leg 68. The legs 66 and 68 are integral with each other and the web 64 of the cylinder bar 24. As will be readily understood by those skilled in the art, the fiange leg 62 and 68 may be considered as constituting an integral backing plate for the cylinder bar 24, and in fact such legs 62 and 68 are shown so used in the attachment of the cylinder bar 24 to the end Walls 26 and 28 and the ring 34. Though not so shown, the cylinder 10 can include conventional backing plates with the flanges 62 and 68 of the cylinder bars 22 and 24 being attached to such backing plates.

It will be noted on further reference to FIGURE 4 that the flange legs 60 and 66 together with the underside of the web 64 define a cavity 70 that underlies the sets of teeth 44 and 46, such cavity 70 opening toward the shaft 12 or axis of the cylinder 10. Cylinder bar constructions whether of the integral or composite type such as to define a cavity in the general nature of the illustrated cavity 70 that open towards the axis of the cylinder are commonplace. The reason for such conventional construction is that the provision of the cavity lessens the cost of the cylinder bars and that less metal is required in their manufacture, a reduction in the overall weight of the combine is obtained, and for the reason that a reduction in weight of the cylinder adjacent the periphery of the same substantially reduces the moment of inertia of the cylinder thereby facilitating the initial rotation of the cylinder.

The provision of the cavity is not without certain disadvantages, the most important of which is that in the nature of dirt, sand, bits of leaves, straw and the like tend to accumulate in the cavities and are retained therein by centrifugal forces. If the accumulation of trash were uniform as between'the various cylinder bars and along the length of each of the individual cylinder bars, the principal disadvantage would be the increase in weight and the increase in the moment of inertia, however, such is not the case. The rate of accumulation of trash in the cavities of the cylinder bars is not uniform as between the various cylinder bars and is not even uniform along the length of individual cylinder bars, whereby serious disadvantages result, namely, the cylinder becomes both statically and dynamically unbalanced to an extent that results in excessive vibration and roughness of operation attended by an unnecessary increase in the rate of wear for the bearing in which the shaft 12 is mounted Such vibration and roughness of operation are still further increased by the fact that occasionally portions of the accumulated trash are suddenly dislodged from various cylinder bars or from a single cylinder bar so as to cause sudden increases in the degree of imbalance of the cylinder. These disadvantages resulting from the provision of cavities underlying the toothed portions of cylinder bars accrue whether or not conventional tooth structures are used or if the illustrated tooth construction is employed.

It has been found that both the tendency of trash to accumulate in the cavity 70 as well as the tendency for abrupt dislodgment of accumulated trash can be greatly reduced upon the provision of means that tends to allow air to pass through and scour the interior of the cavity during motion of the cylinder bar 24 as occasioned by rotation of th cylinder 10. The provision of such means in the preferred and illustrated form of the invention comprises a row of openings 72 extending along the length of the cylinder bar 24, such opening 72 being spaced from each other and extending through the L- shaped flange at the juncture of the legs 60 and 62. As shown, each of openings 72 is preferably somewhat elliptical in configuration with the major axis being parallel to the longitudinal dimension of the cylinder bar 24, and the axis of each of the openings 72 is downwardly inclined to the right as shown in FIGURE 4. Also, as shown in FIGURE 4, it will be seen that each of the openings 72 is preferably divergent downwardly to the right. It is also to be noted that the downwardly inclinded and downwardly diverging openings 72 open into the cavity 70 at or in close proximity to the lower surface of the web 64. It will also be noted that each of the openings 72 constitute an unimpeded opening through the leg 60 in the horizontal direction through a vertical range, and that such vertical range extends from the level of the undersurface of the web 64 to a position below the juncture of the legs 60 and 62. Furthermore, each of the openings 72 extends vertically for a transverse horizontal interval through the leg 62.

A row of openings 74 corresponding to the row of openings 72 is provided through the L-shaped flange constituted of the legs 66 and 68. As shown in FIG- URE 4, each of the openings 74 has an axis inclined downwardly to the left and is downwardly divergent, and as in the case of the openings 72, each of the openings 74 affords an unimpeded horizontal opening for a vertical range extending from the undersurface of the web 64 to a position spaced below the juncture of the legs 66 and 68. Also, as in the case of the openings 72, each of the openings 74 aifords an unimpeded vertical opening for a transverse horizontal distance through the leg 68. As clearly shown in FIGURE 3, each of the openings 74 is generally elliptical shaped with the major axis being parallel to the major dimension of the cylinder bar 24.

In the preferred construction the individual openings 72 and 74 are situated in transverse registry with each other so that during rotation of the cylinder 16 in such a direction as to make the structure shown in FIGURE 4 to be moved to the left the motion of air relative to the cylinder bar 24 is such as to include a stream of air as indicated by the arrows '76 that passes over the leg 62 and through the openings 72, thence through the cavity 70 adjacent the undersurface of the web 64 as indicated by the arrows '78, thence through the openings 74 to pass over the leg 63 as indicated by the arrows 80. While the flow of air through the cavity 70 between the opening 72 and 74 is shown to be generally streamlined, a considerable degree of turbulence is created within the cavity 70 between adjacent air streams so that such air streams andturbulent regions are scoured in a rather efficient manner so as to preclude any substantial accumulation of trash within the cavity 70, and so that such trash as may be accumulated does not build up to any substantial degree without being scoured free and flushed from the cavity 70. It is not essential that the individual opening 72 be in exact transverse registry with the individual openings 74, and it may even be desirable under some circumstances that the openings 72 and '74 be alternately spaced along the length of .the cylinder bar 24 in order to increase the degree of air turbulence created within the cavity 70. With either arrangement of the openings 72 and 74, it will be appreciated that the air scouring action will be equally effective for rotation of the cylinder bar 24 in either the forward or reverse direction. In other words, the design of the means for air scouring the chamber 70 is perfectly compatible with the reversible character of the cylinder bar 24.

Attention is now directed to a modified form of the invention shown in FIGURE 6. The modified cylinder bar shown in FIGURE 6 is designated generally by the reference numeral 82, and the cylinder bar 82 is identical to the cylinder bar 24 except as wherein the same is speciiically hereinafter distinguished. The cylinder bar 82 is identical in the provision of a web 84 (corresponding to web 64), a raised medial portion 86 of the web 84 (corresponding to raised medial portion 55), teeth 88 (corresponding to teeth 46), flanges 9i) and 92 (correspond- 6 ing to legs 60 and 62, and legs 66 and 68), rows of openings 94 and 96 (corresponding to rows of openings 72 and 74), and a cavity 98 (corresponding to cavity 70).

As thus far described the cylinder bar 82 is identical to the hereinbefore described cylinder bar 24. The cylinder bar 82 is distinguished from the cylinder bar 24 in the provision of a depending medial rib 100 that is integral with the web 84 and which is disposed within the cavity 98. The depending medial rib 100 extends the entire longitudinal length of the cylinder bar 82, and terminates at its lower edge in the same general plane as the underside of the flanges 9t) and 92. The depending rib 164 is provided along its length with a row of spaced openings 102 extending transversely therethrough. The openings 102 can be circular in cross section, or if desired can be elliptical in cross section with the major dimension being parallel to the longitudinal dimension of the cylinder bar 82, but in either construction the opening 102 is such that the upper portion thereof is either coincident with or closely spaced to the undersurface of the web 84. In the preferred construction the openings 94, 96 and 100 are all equal in number with the individual openings being equally spaced and with the individual members of such sets of openings being in transverse registry so that air movement through the cylinder bar 82 is generally such as that indicated by the arrows 104, 166, 168 and 110. As in the case of the air streams passing through the cylinder bar 24, the air streams indicated by the arrows 104 through are such that sufficient turbulence is created between adjacent streams through the cavity 98 will occur as to maintain the cavity 98 sufficiently free of trash on both sides of the depending rib 100. As in the case of the cylinder bar 24 it will be readily appreciated by those skilled in the art that the described scouring action by the air streams will be obtained whether the cylinder bar 82 is rotated in either a forward or reverse direction.

Attention is now directed to FIGURE 7 wherein a modified composite cylinder bar construction is designated generally at 112. It will be understood that the cylinder bar construction 112 can, like the cylinder bar construction 82, be used in lieu of the cylinder bar construction 24. The cylinder bar construction 112 is generally similar to the cylinder bar construction 24 and differs primarily in that the same is of two-piece or composite construction rather than being of integral construction. The cylinder bar 112 is comprised of a web 114 integrally connecting L-shaped flanges 116 and 118 so constructed and arranged as to define a cavity 124) intermediate the flanges 116 and 118 that underlies the web 114. Longitudinally extending rows of openings 122 and 124 are provided in the flanges 116 and 118 that are gener ally similar to the rows of openings 72 and 74. A rasp bar 126 such as is disclosed in my US. Patent No, 3,034,- 513 is detachably secured at spaced positions along its longitudinal extent to the web 114 by means of cap screws 128. Inasmuch as the only portion of the composite cylinder bar 114 subjected to appreciable wear is the rasp bar 126, it will be appreciated that the latter can be conveniently replaced after the same has been worn out both during forward and reverse rotation.

The operation of the composite cylinder bar 112 will be readily understood in view of the previous description of the operation of the rasp bar 24. During rotation of a cylinder on which a composite cylinder bar 112 is mounted such that the latter moves to the left as shown in FIG- URE 7, the air moves relative to the cylinder bar 112 in such a manner that an air stream passes through the openings 122 and 124 as well as the cavity as indicated by the arrows 130, 132 and 134 so as to scour the cavity 120. As in the case of the cylinder bar 24, the openings 122 and 124 can be disposed in transverse registry or alternately disposed along the longitudinal length of the cylinder bar 112. In either case, suflicient turbulence is created by adjacent air streams to scour the cavity 120 throughout the longitudinal extent of the latter.

It will be noted with respect to each of the three illus trated embodiments of the present invention that transverse passageways are provided through the cylinder bars that are preferably substantially straight and which pass against or immediately adjacent to the upper confines of the respective cavities. Also, with respect to each of the three illustrated embodiments of the invention, the opposite and outwardly extending flanges or lateral margins of the cylinder bars are so configured as to be directly attachable to the radial elements of the cylinders as shown in FIGURE 1, or to be connected directly to backing plates (not shown) of the cylinder.

As used in the claims, the term reversible used in connection with the rasp bar has reference to the fact that the primary function of the rasp bar (the cooperation of the teeth with the concaves, not shown) will be equally well served whether the rasp bar is reversed in position end for end or not. Applicants US. Patent No. 3,034,513 is exemplary of such a reversible rasp bar. It will be noted that the instant invention will operate equally well for either position of the rasp bar. It will also be apparent to those skilled in the art that the instant invention is also applicable to rasp bars which do not have teeth arranged so that the rasp bar is reversible.

While preferred embodiments of the invention have been illustrated and described in substantial detail, it will be understood that the principles of the invention are susceptiole to numerous variations without departing from the spirit of the invention. Accordingly, attention is directed to the appended claims in order to ascertain the actual scope of the invention.

I claim:

1. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly offset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying the rasp bar that is laterally bounded by adjaeent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising at least one of such flanges being provided with a longitudinally extending row of openings therethrough, said openings being disposed adjacent the juncture of such flange with the rasp bar and opening into said cavity, and said rasp bar being provided with means remote from the openings adapting the rasp bar for being secured to a threshing cylinder with the cavity opening toward the cylinder axis.

2. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly offset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying the rasp bar that is laterally bounded by adjacent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising each of such flanges being provided with a longitudinally extending row of openings therethrough, each of said rows of openings being disposed through said adjacent margins of the flanges and opening into said cavity, and said rasp bar being provided with means remote from the openings adapting the rasp bar for being secured to a threshing cylinder with the cavity opening toward the cylinder axis.

3. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly offset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying the rasp bar that is laterally bounded by adjacent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising at least one of such flanges being provided with a longitudinally extending row of openings therethrough, said openings being disposed adjacent the juncture of such flange with the rasp bar and opening into said cavity, each of said openings having an unobstructed projection horizontally in a direction generally transverse to the longitudinal dimension of the rasp bar that is closely spaced to the lower surface of the rasp bar, and said rasp bar being provided with means remote from the openings adapting the rasp bar for being secured to a threshing cylinder with the cavity opening toward the cylinder axis.

4. The combination of claim 3, wherein the upper side of each opening is inclined upwardly in passing from the cavity through such flange.

5. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly oflset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying the rasp bar that is laterally bounded by adjacent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising each of said being provided with a longitudinally extending row of openings therethrough, said openings being disposed adjacent the junctures of the flanges with the rasp bar and opening into said cavity, said rasp bar having a centrally disposed, longitudinally extending depending rib in said cavity, a longitudinally extending row of horizontal openings through the rib, and said rasp bar being provided with means remote from the openings adapting the rasp bar for being secured to a threshing cylinder with the cavity opening toward the cylinder axis.

6. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly offset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying the rasp bar that is laterally bounded by adjacent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising each of said flanges being provided with a longitudinally extending row of openings therethrough, said openings being disposed adjacent the junctures of the flanges with the rasp bar and opening into said cavity, with pairs of the individual openings of the two rows of openings being parallel in alignment in a direction traversing the rasp bar and inclined to longitudinal dimension of the latter by more than about 45, and said rasp bar being provided with means remote from the openings adapting the rasp bar for being secured to a threshing cylinder with the cavity opening toward the cylinder axis.

7. The combination of claim 6, wherein the angle of inclination is about and wherein the rasp bar is reversible.

8. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, with said rasp bar being provided with downwardly offset, oppositely and laterally extending flanges so as to define a longitudinally extending cavity underlying the rasp bar that is laterally bounded by adjacent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising at least one of such flanges being provided with a longitudinally extending row of openings there through, said openings being disposed adjacent the juncture of such flange with the rasp bar and opening into said cavity, said rasp bar being of two-piece construction and is separable upon a horizontal plane spaced between the bottom of the teeth and the bottom of the rasp bar, with the portion of rasp bar beneath such plane being integral with the flanges, fastening means operable from within the cavity for releasably securing the rasp bar in assembled relation, and said rasp bar being provided with means remote from the openings adapting the rasp bar for being secured to a threshing cylinder with the cavity opening toward the cylinder axis.

9. The combination of claim 1, wherein said openings open directly into the cavity, and wherein the means remote from the openings adapting the rasp bar for being secured to a threshing cylinder comprises said flanges being provided with additional openings therethrough spaced intermediate the lateral extremities of the flanges and the junctures of the latter, such additional openings being adapted to receive means therethrough for securing the rasp bar to a threshing cylinder with the cavity opening toward the axis of the cylinder.

10. In a rasp construction for threshing cylinders of the class including a horizontally disposed and elongated rasp bar having a longitudinally extending row of upstanding teeth thereon, With said rasp bar being provided with downwardly olfset, oppositely and laterally extending flanges so as to define a longitudinally extending cav- 10 ity underlying the rasp bar that is laterally bounded by adjacent margins of the flanges, the combination therewith of means for reducing the accumulation of trash in said cavity comprising at least one of such flanges being provided with a longitudinally extending row of openings therethrough, said openings being disposed adjacent the juncture of such flange With the rasp bar and opening directly into said cavity, rotatable means having a central axis for supporting a plurality of rasp bars for rotation about said axis, and means remote from said openings securing said rasp bar to the rotatable means with the cavity opening toward the axis.

References Cited by the Examiner UNITED STATES PATENTS 1,131,086 3/15 Richardson 27-8 2,256,010 9 41 Ausherman 27--8 5 3,034,513 5/62 Ausherman 130-2785 T. GRAHAM CRAVER, Primary Examiner.

ANTONIO F. GUIDA, ARNOLD RUEGG,

Examiners. 

1. IN A RASP CONSTRUCTION FOR THRESHING CYLINDERS OF THE CLASS INCLUDING A HORIZONTALLY DISPOSED AND ELONGATED RASP BAR HAVING A LONGITUDINALLY EXTENDING ROW OF UPSTANDING TEETH THEREON, WITH SAID RASP BAR BEING PROVIDED WITH DOWNWARDLY OFFSET, OPPOSITELY AND LATERALLY EXTENDING FLANGES SO AS TO DEFINE A LONGITUDINALLY EXTENDING CAVITY UNDERLYING THE RASP BAR THAT IS LATERALLY BOUNDED BY ADJACENT MARGINS OF THE FLANGES, THE COMBINATION THEREWITH OF MEANS FOR REDUCING THE ACCUMULATION OF TRASH IN SAID CAVITY COMPRISING AT LEAST ONE OF SUCH FLANGES BEING PRO- 